The canonical tag was one of the handiest developments in SEO in a long time. It’s thanks to this useful piece of information in the header of our websites that we can essentially eliminate any duplication that might be occurring without needing to go through the development teams to get 301 redirects handled (how many times does it turn out to be a 302?). Unfortunately, as with all things, there’s a lot that can go wrong with them, especially if the people putting them in aren’t quite sure what they’re doing.

If you’ve been in the game for a while, you’ve probably seen some shockingly bad implementations of them. I know I have. Today, I’m going to talk through a few of them.